The present invention relates to a texture mapping method in a design simulator or the like.
In these years, simulation to know what the appearance of the object looks like when a specified texture is applied onto a surface of an object, has been increasingly carried out with the help of a computer. This simulation technique, which can easily study the interior decoration, appearance and so on of an article, is very effective compared with a prior art of actually manufacturing a model troublesomely to know the appearance of the object. This technique is called texture mapping in computer graphics and disclosed, for example, in a book entitled "Procedural Elements for Computer Graphics", Chapter 5, Section 11, David F. Rogers, McGraw-Hill Book Company, 1985 (which will be referred to merely as the prior art 1, hereinafter).
In the texture mapping explained in the prior art 1, it is assumed that a strict three-dimensional shape (configuration) on a surface of an object to be applied with a texture is previously known. When the three-dimensional shape data are used and mathematically calculated, it is possible to know how to distort the texture to allow the texture to be applied onto the object surface. In the case where the strict three-dimensional shape is not known, the shape has so far been. assumed to perform texture mapping and additional processing has been carried out on a trial and error basis while observing the resultant picture, in many cases.
In the prior art 1, in the event where a surface shape (configuration) of an object to be mapped is not known, it is impossible to realize favorable texture mapping. That is, the prior art 1 has had such a problem that, since a three-dimensional surface shape of an object in an ordinary picture is not known in many cases, the application range of such a prior art technique as mentioned above is restricted.